• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14
  15. 15
  16. 16
  17. 17
  18. 18

Record the effect that the enzyme catalase found inside the potato has, when added to hydrogen peroxide, and whether to not there is a change in the rate of reaction when the surface area of the potato is increased.

Extracts from this document...


PLANNING Enzymes Background Information Enzymes such as catalyse are protein molecules, which are found in living cells. They are used to speed up specific reactions in the cells. They are all very specific as each enzyme just performs one particular reaction. Catalyse is an enzyme found in food such as potato and liver. It is used for removing Hydrogen Peroxide from the cells. Catalyse speeds up the decomposition of Hydrogen Peroxide into water and oxygen. It is able to speed up the decomposition of Hydrogen Peroxide because of the shape of the Hydrogen Peroxide molecule. This type of reaction where a molecule is broken down into smaller pieces is called an anabolic reaction. Aim: Carry out an experiment on enzyme activity. The aim is to record the effect that the enzyme catalase found inside the potato has, when added to hydrogen peroxide, and whether to not there is a change in the rate of reaction when the surface area of the potato is increased. Apparatus: Apparatus * Hydrogen peroxide (H202) of 20 volume * Ruler * Measuring cylinder 150ml * Potato * Stop watch * Goggles * Beakers of various sizes Arrangement of our experiment: Fair Test We must ensure that the experiment is a fair test. To do this we are going to take use of the same apparatus. The only variables to be changed is the surface area of the potatoes and we will repeat the investigation two times. ...read more.


Enzymes are the catalysts in biological processes. They are large proteins that speed up chemical reactions. The enzyme forms the active site from small numbers of amino acids. The active site is the location on the enzyme where the substrate collides and the reaction takes place. If the shape of and the substrate do not match exactly then they do not bind. This makes sure that the enzyme does not work with the wrong reaction. Enzymes are not affected by the reaction, so when the products have been released, the enzyme is ready to bind with a new substrate. In my experiment the substrate was the hydrogen peroxide, the enzyme that we used was hydrogen peroxide and the product that was formed was oxygen and water. This can be explained by an equation: Enzyme + Substrate � Product In my experiment this is shown as: Catalase + H202� H202 + 02 This equation explains how the catalase in our experiment binded with the H202 to break it down and form oxygen. Induced Fit Theory The induced fit theory states that the binding of a substrate to an enzyme causes a change in the shape of the enzyme. The enzyme and the substrate act on each other to affect the making of the active site to the usual complex between the enzyme and its substrate. As a result, this means the enzyme to catalyze a reaction has changed. This shows that enzymes are specific for specific substrates. ...read more.


I will keep constant are: -Amount of hydrogen peroxide - Temperature of the hydrogen peroxide - Concentration of the hydrogen peroxide - Mass of the piece of potato - Type and age of the potato - Apparatus used The above list of controlled variable will ensure I have a fair test to give accurate results. And I will repeat the experiment again to make sure. So to sum it up the variables, what will be measured, is due to the change surface area. Thus I have made a plan set fourth in accordance to all the information above: 1) Collect all the right apparatus. 2) Set the experiment in a free space zone area. 3) Cut the potatoes to the various sizes from the received 4cm potato. 4) Measure out 20cm3 of hydrogen peroxide by using a measuring cylinder. 5) Receive test tube and pure in the hydrogen peroxide and the various potato sizes. 6) Wait for four minutes. 7) Then get a ruler. 8) Measure the length of the froth. 9) Afterwards, dispose of the potato into a bin, and clear the surfaces you have worked on. 10) Repeat for all left sizes. This is the method I am going to use for every potato size. By carrying out all the things, which I have listed, I will be able to establish precisely that my test has been fair. I will be able to prove this by saying all materials and apparatus have been handled and used with the same treatment, and in an overall fair manner. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Patterns of Behaviour essays

  1. Factors Affecting the Rate of Catalytic Decomposition of Hydrogen Peroxide.

    0.53 0.53 30 0.63 0.63 0.63 35 0.69 0.68 0.69 40 0.77 0.76 0.77 45 0.78 0.76 0.77 50 0.78 0.76 0.77 55 0.78 0.76 0.77 1.76 mol Reading 1 Reading 2 Average Time (s) Mass Lost (g) Mass Lost (g)

  2. The effect of aspirin on the action of bovine liver catalase

    This supports the hypothesis that aspirin is an inhibitor of bovine liver catalase. Because nobody has fully investigated the enzyme inhibiting properties of aspirin, it is unknown whether the inhibition is competitive or non-competitive, or active site directed or non-active site directed.

  1. Influence of pH on the Activity of Potato Catalase.

    pH Average Time/Seconds 2.8 104.2 3.5 83.64 4.3 81.90 6.3 22.03 8.3 31.20 Rate of Reaction: The rate of reaction for the experiment was calculated by using two formulae: A = ? R� and Rate of Reaction = Volume Time So, Gas Produced = 3.14 x 1.5� this provides the

  2. To determine the rate law for a chemical reaction among hydrogen peroxide, iodide and ...

    + I2(aq) --> 2I-(aq) + S4O62-(aq) ; the use of Na2S2O3(aq) in Part II is related to a name called "clock reaction" Ans: Na2S2O3 has two functions in part II. Firstly, the thiosulphate reacts with the iodine as in the following equation: 2S2O32-(aq)

  1. An Investigation of the Effect of Copper Sulphate on Catalase Activity.

    over time Graph 3. A graph to show the mean amount of oxygen produced, when the copper sulphate solution concentration was zero, over time. This graph is included as an example of how the initial rate of reaction was calculated by working out the gradient of the line at 30 seconds.

  2. The Effect of Catalase in the Breakdown of Hydrogen Peroxide

    This would then tell me which of the percentages would be best appropriate for my actual experiment. In addition; after comparing the differenced between the peeled and unpeeled potato, I can then choose, which I would then use for my actual experiment.

  1. Free essay

    Close Your Eyes

    I thought that I would scare her so I snuck up behind her, making sure she couldn't hear me and prepared to put my hands on either side of her waist. She was listening to whoever was on the other end of the phone, really focusing on what they were saying and all of a sudden she spoke.

  2. Enzymes - show how substrate concentration affects the rate of reaction for an enzyme ...

    This very important as the rate of reaction is dependant on temperature hence I will have to make sure that temperature is controlled. So therefore in order to limit the error by maintaining temperature at constant I will be using a thermostatically controlled water bath.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work